The synthesis of many organic compounds involves a hydrogenation step. By this step an unsaturation, mostly a C=C configuration, is converted into a CH--CH configuration in the presence of hydrogen. This important reaction is carried out by simultaneously contacting the compound to be hydrogenated with a catalyst, e.g., nickel, and with hydrogen.
It is also known to hydrogenate phenol to form cyclohexanol. However, this reaction also produces a certain quantity of cyclohexanone. Generally speaking, the problem exists to hydrogenate hydroxy-substituted carbocyclic aromatic compounds to the corresponding saturated alicyclic alcohols with high yield of alcohols but with little or no production of the corresponding cyclic ketone.